This invention relates to synthetic inorganic phosphors. More particularly, the invention relates to compounds of ytterbium activated hafnium oxide which emit light in the green region of the spectrum under excitation with suitable radiation. This radiation includes both long and short wavelength ultraviolet x-radiation and cathode rays.
Phosphors are known products of commerce. Generally, the term is employed in the art to describe luminescent or fluorescent solids which comprise two essential ingredients: a host matrix; and an activator. Such phosphors are employed in color cathode ray tubes, fluorescent lamps, x-ray tubes and both high pressure and low pressure mercury vapor lamps.
It would be an advance in the art to discover new materials which would be useful in the above applications.